1. Field of The Invention
The present invention relates to the field of structural pest control. The invention relates more specifically to the control, prevention and eradication of subterranean pests in structures. Preferably, the present invention controls termite infestation in structures, namely households, commercial buildings and other structures where there exists a void or small space behind a stucco, brick, block, wood or any other type of exterior or veneer finish.
2. Background
Conventional pest control systems have been found to be ineffective in many situations. Damage caused to structures because of ineffectual pest control causes the significant loss of integrity to structures, and can cost property owners a significant amount in remediation measures.
Termites present a particular problem for structures that have foam insulation covered by a stucco veneer. Termites use the void area behind the stucco veneer as a hidden pathway into the structure in their search for food and moisture. In this fashion, termites can cause their damage while remaining undetected for years in the void area behind the veneer.
While the disclosure herein focuses particularly on termite control, other pests cause structural damage in similar ways, for example, carpenter ants and the like, and that the present invention is also designed to control these pests.
Subterranean termites cause damage to more American homes each year than damage incurred by fires, lightening, tornadoes, and hurricanes, combined. Termites infest every state in the United States except Alaska. In one acre of land, there may be as many as a dozen termite colonies. While most people believe that termites attack only structural wood members, they will, in fact, attack anything that contains cellulose, for example, books, carpets, drywall, flooring, subflooring, fabrics, furniture, trim, window frames and more.
Termites can cause extensive damage before they are ever discovered because they work silently and remain hidden from view. Termites are creatures perfectly adapted for what they can do, the degradation of cellulose. With present control systems, it is virtually impossible to fully destroy a termite colony. Their subterranean nests are nearly impossible to locate and, therefore, cannot be eliminated by traditional treatment methods. It has been estimated that as many as 245,000 termites comprise a single colony, making their numbers far too great to be entirely eliminated with a single pest control application.
Presently, termite treatment methods focus on creating a chemical barrier between the structure to be protected and the surrounding soil. Since subterranean termites require moisture to survive, termites frequently seek out a source of moisture. They find moisture in both the ground and cellulose, which leads them ultimately to find the structure. It is assumed that by creating a barrier under and around the structure, new termites cannot enter inside it and termites already inside die due to the lack of moisture.
Chlorinated hydrocarbons were once the primary chemical weapon used to fight termites. Recently, though, they were removed from the market. Since 1987 when chlorodane, a chlorinated hydrocarbon, was taken off the market, the number of termite retreatments required has increased significantly due to the failure of present chemical barriers. The termiticide chemicals used today are just not as effective as the chlorinated hydrocarbons used in the past.
Several building techniques utilizing foam insulation have been known since the early 1980's and have particular pest control problems as discussed previously. By 1992 it was estimated that 50% of new buildings use some type of foam insulation. Unfortunately, problems with termite infestations arise when, as a continuous sheet, foam insulation is placed with portions of it resting below grade. Termites can use the below grade foam insulation as a highway into the structure by tunneling through the foam, or between the foam and masonry. The termites remain undetected until severe damage has occurred because the insulation is hidden from view by, e.g., a stucco veneer.
This type of infestation is a serious problem for Exterior Insulation and Finish Systems (EIFS). EIFS are multi-component exterior wall systems which generally comprise an insulation board; an adhesive or mechanical attachment of the insulation board to the substrate or existing wall surface; a base coat reinforced with fiber glass mesh on the face of the insulation board; and, a finish coat which protects the entire system and which can be applied in a wide variety of colors and textures. Synthetic stucco and various mortar type mixes are also referred to as the EIF System. A disadvantage in the installation of this wall system is that it may allow moisture damage if not properly finished.
3. EIFS
Adhesives are most often used to anchor the insulation board to the substrate. Mechanical fasteners are particularly recommended when the substrate type or condition prevents adhesion. Attachments are designed to resist wind, gravity, and the effects of thermal movement.
Insulation boards are the basic building blocks of low-cost creative architectural shaping. At R-3.8-5.6 per inch, they also make EIFS presently one of the most energy-efficient wall systems available. Exterior insulation creates an unbroken casing, preventing thermal bridging through studs and outlets. Insulation boards allow for expansion and contraction while maintaining the integrity of the finish.
The base coat applied on the outside of the insulation boards creates a vapor permeable barrier against weather and reinforces the exterior surface against impact. It envelopes the exterior, and teamed with insulation board, greatly reduces air infiltration and thus energy consumption.
The primer promotes adhesion and reduces the chance of efflorescence. It improves and stabilizes the color and appearance of the finish. The finishes may be a decorative textured finish applied over the base coat and primer. It is integrally colored and formulated with 100% acrylic polymers to resist UV effect.
EIFS began in Sweden in the 1940's. It was simply a form of plaster that was isolated from the movement of the building by a layer of mineral wool. This isolation minimized cracking. Soon thereafter, similar systems began to be used in other parts of Europe. In the 1960's the system which incorporates rigid polystyrene and mesh-reinforced coatings started being used in Germany. In 1969, it was introduced in the United States. EIFS products did not see widespread use in residential frame construction until the mid 1980's. As the product was being developed and marketed in the United States, modifications began to be made in the system. Marketing and product engineering evolved the product into what is now know as EIFS or synthetic stucco. Currently, EIFS is the terminology used to describe a modem stucco-like construction technique.
Synthetic stucco may be an acrylic polymer which is applied over the fiberglass mesh. The mesh covers the foam insulation board, which is typically attached to a gypsum sheating board, plywood or masonry wall. The gypsum sheating and the plywood are typically nailed to wood framing. The fiber glass mesh is coated with the base coat and the finish coat of acrylic, to resemble stucco.
Termite problems arise when the synthetic stucco is installed improperly. Moisture can enter the structure through small cracks in the synthetic stucco and through cracks around poorly caulked windows, doors, sealed joints and flashing. Once behind the synthetic stucco surface, water is trapped because of the low permeability of the stucco and the foam board insulation.
Rigid board insulation, foam board and other similar material such as polystyrene, polyisocyanurate (collectively referred to as "RBI") and synthetic stucco when used or installed improperly may lead to the following problematic conditions:
(A) The retention of moisture in walls. Cracks around windows, doors, sealed joints and flashing as well as small cracks in the surface of synthetic stucco will allow moisture in the form of rain, snow, or condensation, to enter behind the synthetic stucco or RBI and remain trapped there. The presence of moisture in proximity to wood is a condition which is conducive to infestation by, among others, subterranean termites, wood decay fungi and carpenter ants. The trapped moisture allows subterranean termites to remain above ground without a need to return to the soil. Excess moisture in wood leads to wood decay. In addition, carpenter ants often excavate and nest in wood. Even when not installed at or below grade, RBI and synthetic stucco may retain moisture in walls.
(B) The inability to detect wood destroying organism infestations. When used at or below ground level, the above building materials may make detection of wood destroying organisms virtually impossible in the early stages of degradation. While termites do not gain nourishment from the RBI, they readily tunnel through it in order to reach the structural wood. Oftentimes, the RBI is hidden behind siding, providing a hidden pathway which allows subterranean termites to reach structural wood undetected.
(C) The inability to properly treat the structure for wood destroying organism infestation and to protect it from wood destroying organism damage. If the structure is to be protected by a barrier treatment, soil adjacent the exterior of the RBI and synthetic stucco must be treated with termiticide down to the footer. If termiticide does not reach to the footer, the soil beneath the RBI/synthetic stucco must be further treated to prevent subterranean termites from tunneling up from the soil beneath to reach the structural wood by tunneling between the RBI and synthetic stucco, and the foundation wall. Yet oftentimes, it is neither feasible nor possible to treat underneath the bottom of RBI and synthetic stucco which extend deep into the soil (i.e. basement homes) and when RBI has been used underneath a slab.
Thus it can be seen that there is a need for an effective pest control system, and, more specifically, a subterranean termite control system that can conveniently, effectively and consistently control termite infestations. It is to the provision of such a method and apparatus that the present invention is primarily directed.